CVE-2020-35681 Django Channels leakage of session identifiers using legacy AsgiHandler

High 7.4 Published Updated

Remote attackers can obtain sensitive information like session identifiers due to improper request scope separation in legacy HTTP handlers.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Over the internet
Victim action needed
Not needed
Fix
Available

What is CVE-2020-35681?

CVE-2020-35681 is a high-severity vulnerability in n/a, published on 22 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Django Channels 3.x before 3.0.3 allows remote attackers to obtain sensitive information from a different request scope. The legacy channels.http.AsgiHandler class, used for handling HTTP type requests in an ASGI environment prior to Django 3.0, did not correctly separate request scopes in Channels 3.0. In many cases this would result in a crash but, with correct timing, responses could be sent to the wrong client, resulting in potential leakage of session identifiers and other sensitive data. Note that this affects only the legacy Channels provided class, and not Django's similar ASGIHandler, available from Django 3.0.

Weakness: CWE-200

Which versions are affected by CVE-2020-35681?

3 open source packages ship an affected version, including channels. It affects 1 product.

PackageAffectedFixed in
channels PyPIFrom 3.0.03.0.3
channels PyPIFrom 3.0.03.0.3
channels PyPIFrom 3.0.03.0.3

Products include Djangoproject Channels.

How do I fix CVE-2020-35681?

Upgrade channels to 3.0.3 or later.

Is CVE-2020-35681 being exploited?

There is no known exploitation of CVE-2020-35681 in the wild and no public exploit code.

Sources

Also known as DEBIAN-CVE-2020-35681, GHSA-v542-8q9x-cffc, PYSEC-2021-113, UBUNTU-CVE-2020-35681.

Is CVE-2020-35681 in your software?

Upload an SBOM and sbomify checks it against every vulnerability here, every day.

Check your SBOMs for free